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Background: Some dietary factors have been associated with the risk of type 1 diabetes in childhood. Objective: We investigated relations between dietary energy from major food groups and incidence of childhood type 1 diabetes by using an ecologic study design. Design: We conducted univariate and multivariate regression analysis with incidence rates of type 1 diabetes in the late 1980s and early 1990s among children aged < 15 y in 40 countries as the dependent variable and average per capita daily intake of major food items and other socioeconomic, demographic, and geographic risk factors as the independent variables. Results: In the univariate regression model, per capita total energy intake was nonsignificantly associated with type 1 diabetes incidence (r = 0.31, NS), whereas energy from animal sources was associated (r = 0.61, P < 0.01) and energy from vegetal sources was inversely associated (r = Ϫ0.35, P < 0.05) with diabetes incidence. Among dietary items of animal origin, meat (r = 0.55, P < 0.001) and dairy products (r = 0.80, P < 0.0001) were predictors of elevated incidence rates, whereas among dietary items of vegetal origin, cereals (r = Ϫ0.64, P < 0.001) were inverse predictors. In the multivariate analysis, the inverse relation of diabetes incidence with energy from vegetables and the direct correlation with energy from animal sources explained the positive associations of type 1 diabetes incidence with geographic and socioeconomic covariates. Conclusion: The incidence of type 1 diabetes varied worldwide according to dietary patterns. In-depth exploration of dietary risk factors during pregnancy and early neonatal life is warranted to confirm whether and to what extent diet cooperates with genetic susceptibility in the early onset of type 1 diabetes.Am J Clin Nutr 2000;71:1525-9.

Objectives-To study the role of dust exposure on incidence of respiratory symptoms and decline of lung function in young coal miners. Methods-The loss of lung function (forced vital capacity (FVC), forced expiratory volume in one second (FEV,), forced expiratory flow (MEF), carbon monoxide transfer factor (TLCO)) with time and the incidence of respiratory symptoms in 909 Sardinian coal miners (followed up between 1983 and 1993 with seven separate surveys) has been compared with the past and current individual exposures to respirable mixed coal dust. Multiple linear and logistic regression models were used simultaneously controlling for age, smoking, past occupational exposures, and other relevant covariates. Results-According to the relatively low dust exposures experienced during the follow up few abnormal chest x ray films were detected. In the cross sectional analysis ofinitial data, significant associations between individual cumulative exposure to dust, decrements in FEV, and MEFs, and increasing prevalence of respiratory symptoms were detected after allowing for the covariates included in the model.The yearly decline of FVC, FEV,, and single breath carbon monoxide transfer factor (TLCOIVA) was still significantly related to the individual exposure to dust experienced during the follow up, even after allowing for age, smoking, initial cumulative exposure to dust, and initial level ofeach functional variable. In logistic models, dust exposure was a significant predictor of the onset of respiratory symptoms besides age and smoking. Conclusions-The results show that even moderate exposures to mixed coal dust, as in our study, significantly affect lung function and incidence of symptoms of underground miners. Although the frequency of chest x ray examination might be fixed at every three or four years, yearly measurements of lung function (spirometry, MEFs, and TLCo) are recommended for evaluation of the respiratory risk from the coal mine environment to assess the need for further preventive interventions.(Occup Environ Med 1996;53:312-319)

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Objectives-To evaluate the association between silica, silicosis and lung cancer, the mortality of 724 patients with silicosis, first diagnosed by standard chest x ray film between 1964 and 1970, has been analysed by a cohort study extended to 31 December 1997. Methods-Smoking and detailed occupational histories were available for each member of the cohort as well as the estimated lifetime exposure to respirable silica dust and radon daughters. Two independent readers blindly classified standard radiographs according to the 12 point International Labour Organisation (ILO) scale. Lung function tests meeting the American Thoracic Society's criteria were available for 665 patients. Standardised mortality ratios (SMRs) for selected causes of death were based on the age specific Sardinian regional death rates. Results-The mortality for all causes was significantly higher than expected (SMR 1.35, 95% confidence interval (95% CI) 1.24 to 1.46) mainly due to tuberculosis (SMR 22.0) and to non-malignant chronic respiratory diseases (NMCRD) (SMR 6.03). All cancer deaths were within the expected numbers (SMR 0.93; 95% CI 0.76 to 1.14). The SMR for lung cancer was 1.37 (95% CI 0.98 to 1.91, 34 observed), increasing to 1.65 (95% CI 0.98 to 2.77) allowing for 20 years of latency since the first diagnosis of silicosis. Although mortality from NMCRD was strongly associated to the severity of radiological silicosis and to the extent of the cumulative exposure to silica, SMR for lung cancer was weakly related to the ILO categories and to the cumulative exposure to silica dust only after 20 years of lag interval. A significant excess of deaths from lung cancer (SMR 2.35) was found among silicotic patients previously employed in underground metal mines characterised by a relatively high airborne concentration of radon daughters and among ever smokers who showed an airflow obstruction at the time of the first diagnosis of silicosis (SMR 3.29). Mortality for lung cancer related to exposure was evaluated with both the Cox's proportional hazards modelling within the entire cohort and a nested case-control study (34 cases of lung cancer and 136 matched controls). Both multivariate analyses did not show any significant association with cumulative exposure to silica or severity of silicosis, but confirmed the association between mortality for lung cancer and relatively high exposure to radon, smoking, and airflow obstruction as significant covariates. Conclusions-The findings indicate that the slightly increased mortality for lung cancer in this cohort of silicotic patients was significantly associated with other risk factors-such as cigarette smoking, airflow obstruction, and estimated exposure to radon daughters in underground mines-rather than to the severity of radiological silicosis or to the cumulative exposure to crystalline silica dust itself. (Occup Environ Med 2001;58:786-793)